Q: After fuel pump replacement, no power getting to fuel pump - 1991 Toyota Supra Automatic

asked by on September 10, 2016

My car was running on starter fluid and needed a fuel pump. I replaced the pump and cleaned the gas tank. Next, I tried to start the car and there was absolutely no power to the fuel pump. To make sure that the new fuel pump was working, I hooked it up to the tail lights and it worked. It pumps fuel to the engine, but I’m not getting any spark. A mechanic told me that most of the engine is not getting power. Except for the ignition and the alternator, everything else is not getting power. He also told me that the security light was on. I’m using a spare key that I had made to lock and unlock the doors. A friend told me that using that key in that way might have activated the security system and shut off power down to the engine. What is your diagnosis and how can I fix it?

I would start with clearing the security issue, because utilizing the wrong key (or a bad door sensor) can disable the fuel injection and fuel pump once the security system arms, as your mechanic notes. Once the security system is verified to be working properly, and out of the picture, make sure fuel injection, ignition and fuel pump fuses/relays are working properly, routing power to the ignition, injection computer and fuel pump. A YourMechanic professional can help diagnose this issue and get you on your way!

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